Fire Effects Information System (FEIS)
FEIS Home Page

Index of Species Information



AUTHORSHIP AND CITATION : Snyder, S. A. 1991. Canis lupus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: [].
ABBREVIATION : CALU COMMON NAMES : gray wolf grey wolf timber wolf eastern timber wolf Rocky Mountain wolf lobo buffalo wolf brown wolf TAXONOMY : There are 32 subspecies of gray wolf worldwide; 24 of these occur in North America. They are differentiated by size, weight, color, cranial measurements, and geographic location [16,22,34]. However, these characteristics vary within each subspecies. Also their ranges can overlap and interbreeding occurs. Mech [22] stated that too many subspecies have been identified, and that some were distinguished from a small, insignificant sample size. All 24 North American subspecies are listed below. Those thought to be extinct are marked with an asterisk. Canis lupus alces Canis lupus arctos, American arctic or arctic tundra wolf Canis lupus baileyi, Mexican gray wolf Canis lupus beothucus*, Newfoundland wolf Canis lupus bernardi, Banks Island tundra wolf Canis lupus columbianus, Northern Rocky Mountain wolf Canis lupus crassodon Canis lupus fuscus*, Cascade wolf Canis lupus griseoalbus, Saskatchewan timber wolf Canis lupus hudsonicus, Hudson Bay wolf Canis lupus irremotus Canis lupus labradorius, Labrador wolf Canis lupus ligoni, Alexander Archipelago wolf Canis lupus lycaon Canis lupus mackenzii Canis lupus manningi Canis lupus mogollonensis*, Mogollon Mountain wolf Canis lupus monstrabilis*, Texas gray wolf Canis lupus nubilus*, plains wolf Canis lupus occidentalis, British Columbia wolf Canis lupus orion, Greenland wolf Canis lupus pambasileus, northern timber wolf Canis lupus tundrarum, barren ground or arctic wolf Canis lupus youngi*, Southern Rocky Mountain wolf ORDER : Carnivora CLASS : Mammal FEDERAL LEGAL STATUS : The gray wolf is generally listed as Endangered, with some exceptions. Populations in Minnesota are listed as Threatened; those in Wyoming are listed as an Experimental Population, Non-Essential; and those in the Northern Rocky Mountains have been delisted [30]. Mexican gray wolves are generally listed as Endangered. Those in portions of Arizona and New Mexico are listed as an Experimental Population, Non-Essential [30]. OTHER STATUS : More information on the state-level protection status of gray wolves in the United States is available at NatureServe, although recent changes in status may not be included.


GENERAL DISTRIBUTION : The gray wolf is found worldwide, ranging from across Europe to northern Asia; however, it has been extirpated from much of its former range. Formerly in North America, the gray wolf ranged from the southern fringe of Greenland south through mid-Mexico and from the Atlantic to the Pacific [34].  It occupied almost all regions of the United States except for deserts and high mountaintops [22,34].  Today the gray wolf occupies about 1 percent of its former range in the contiguous states [10].  It occupies northeastern Minnesota, northern Wisconsin, the Upper Peninsula of Michigan, northwestern Montana, central Idaho, and Washington's Cascade Mountains.  In addition the gray wolf is abundant throughout Alaska and Canada.  The ranges for the 24 subspecies follow [22,34]: Ssp. irremotus - Idaho, western Montana, Wyoming, Alberta, and the                  western fringes of Washington and Oregon Ssp. columbianus - British Columbia and southwestern Alberta; can                    move into the northwestern states Ssp. occidentalis -  northern Alberta and Saskatchewan,                      northeastern British Columbia, and central                      Manitoba, into the Yukon and the Northwest                      Territories Ssp. lycaon - southeastern Manitoba, Ontario, Quebec, and the               eastern United States, from the Atlantic to               central Minnesota, south to northeastern Florida Ssp. nubilus - thought to be extinct, although it may possibly                occur in Minnesota [19]; from southern Manitoba                and Saskatchewan, south through the Great Plains                into northern Texas Ssp. alces - the Kenai Peninsula, Alaska Ssp. pambasileus - Yukon Territory and all but northern Alaska Ssp. tundrarum - northern Alaska Ssp. hudsonicus - along the Hudson Bay in the Northwest                   Territories and Manitoba Ssp. arctos - Melville Island, Northwest Territories Ssp. orion - Greenland Ssp. labradorius - northern Quebec and Newfoundland Ssp. beothucus - the island of Newfoundland Ssp. ligoni - Alexander Archipelago, Alaska Ssp. fuscus - the Cascade Mountains of Washington, Oregon, and               California Ssp. crassodon - Vancouver Island, British Columbia Ssp. youngi - the southern Rocky Mountains of Utah, Arizona,               New Mexico, Colorado, and Wyoming Ssp. mogollonensis - central Arizona and westcentral New Mexico Ssp. monstrabilis - Texas, Mexico, and southeast New Mexico Ssp. baileyi - central Mexico into southern Arizona and                New Mexico Ssp. bernardi - Banks and Victoria Islands, Northwest Territories Ssp. mackenzii - northern Northwest Territories and Yukon Territory Ssp. manningi - Baffin Island, Northwest Territories Ssp. griseoalbus - Alberta, Saskatchewan, Manitoba, Northwest                    Territories, and Newfoundland ECOSYSTEMS : FRES10 White-red-jack pine FRES11 Spruce-fir FRES18 Maple-beech-birch FRES19 Aspen-birch FRES20 Douglas-fir FRES21 Ponderosa pine FRES22 Western white pine FRES23 Fir-spruce FRES24 Hemlock-Sitka spruce FRES25 Larch FRES26 Lodgepole pine FRES36 Mountain grasslands FRES37 Mountain meadows STATES :
BLM PHYSIOGRAPHIC REGIONS :     2  Cascade Mountains     8  Northern Rocky Mountains     9  Middle Rocky Mountains    16  Upper Missouri Basin and Broken Lands KUCHLER PLANT ASSOCIATIONS :    K003  Silver fir - Douglas-fir forest    K004  Fir - hemlock forest    K008  Lodgepole pine - subalpine forest    K010  Ponderosa shrub forest    K011  Western ponderosa forest    K012  Douglas-fir forest    K013  Cedar - hemlock - pine forest    K014  Grand fir - Douglas-fir forest    K015  Western spruce - fir forest    K093  Great Lakes spruce - fir forest    K094  Conifer bog    K095  Great Lakes pine forest    K096  Northeastern spruce - fir forest    K106  Northern hardwoods    K107  Northern hardwoods - fir forest SAF COVER TYPES :      1  Jack pine      5  Balsam fir     12  Black spruce     13  Black spruce - tamarack     15  Red pine     16  Aspen     17  Pin cherry     18  Paper birch     20  White pine - northern red oak - red maple     21  Eastern white pine     24  Hemlock - yellow birch     25  Sugar maple - beech - yellow birch     30  Red spruce - yellow birch     33  Red spruce - balsam fir     35  Paper birch - red spruce - balsam fir     37  Northern white cedar     38  Tamarack    107  White spruce    108  Red maple    201  White spruce    202  White spruce - paper birch    203  Balsam poplar    204  Black spruce    205  Mountain hemlock    206  Engelmann spruce - subalpine fir    208  Whitebark pine    210  Interior Douglas-fir    211  White fir    212  Western larch    213  Grand fir    215  Western white pine    217  Aspen    218  Lodgepole pine    220  Rocky Mountain juniper    221  Red alder    222  Black cottonwood - willow    223  Sitka spruce    224  Western hemlock    225  Western hemlock - Sitka spruce    230  Douglas-fir - western hemlock    235  Cottonwood - willow    237  Interior ponderosa pine    253  Black spruce - white spruce    254  Black spruce - paper birch SRM (RANGELAND) COVER TYPES : NO-ENTRY PLANT COMMUNITIES : Gray wolves inhabit a variety of plant communities.  Their territories usually contain a mix of forested and open areas.  Gray wolves can also be found on the tundra.  In the West, gray wolves have been known to follow ungulate herds from their lowland wintering grounds to their high summer pastures [16].  In the East, gray wolves inhabit a mix of coniferous and deciduous forests, which include balsam fir (Abies balsamea), black spruce (Picea mariana), white spruce (P. glauca), white-cedar (Thuja occidentalis), jack pine (Pinus banksiana), white pine (P. strobus), red pine (P. resinosa), tamarack (Larix laricina), sugar maple (Acer saccharum), yellow birch (Betula alleghaniensis), and eastern hemlock (Tsuga canadensis).  In the West, gray wolves inhabit Douglas-fir (Pseudotsuga menziesii)-spruce (Picea spp.) forests, as well as ponderosa pine (Pinus ponderosa) and western larch (Larix occidentalis) forests [16,23,28].


TIMING OF MAJOR LIFE HISTORY EVENTS : Mating - occurs from January to April Gestation Period - 63 days Litter Size - average five to six pups; weaned at 5 weeks Breeding Age - 2 years, but often do not breed until 3 years due to                social structure of the pack; usually only dominant                male and female breed Life Span - up to 16 years, but 10 years is considered quite old Pack Size - averages 2 to 15 individuals, although 36 individuals have             been reported; packs structured in a dominance hierarchy [10,21,22,35] PREFERRED HABITAT : Gray wolves' habitat preferences appear to be more prey dependent than cover dependent.  Herman and Willard [16] summarized that gray wolves choose home territories with a variety of topographic features.  Forests, open meadows, rocky ridges, and lakes or rivers all comprise a pack's territory.  In the West gray wolves have been known to follow the seasonal elevational movements of ungulate herds [16].  In Minnesota, where territories encompass only subtle elevational changes, Fritts and Mech [10] observed no changes in territory use by gray wolves between summer and winter.  In south-central Alaska Ballard and others [1] found that gray wolves do not follow migrating moose or caribou outside of their pack territories.  Gray wolves do, however, follow moose and caribous' elevational movements within pack territories. COVER REQUIREMENTS : Gray wolves excavate natal dens in well-drained soils in meadows near water [16].  They may use the same den for several years.  In Minnesota Fuller [11] found gray wolves denning in hollow logs (24 to 35 inches [60-90 cm] diameter).  Gray wolves also den under tree roots, rock outcrops, or even in beaver lodges [11].  After 1 to 2 months these natal dens are abandoned for an open area called a rendez-vous site.  Here the pups are guarded by a few adult pack members, while the rest of the pack hunts [1]. Herman and Willard [16] summarized that gray wolves need a large, remote area relatively free from human disturbance.  Territory sizes range from 20 to 215 square miles (54-555 sq km) in Minnesota [10].  Average territory sizes in Minnesota have been reported to vary from 55 to 120 square miles (143-310 sq km) [29] and 25 to 29 square miles (64-75 sq km) [2]. In the West average territory sizes vary from 75 to 150 square miles (194-388 sq km) and are smaller in winter when ungulates are concentrated on their wintering grounds [16]. FOOD HABITS : Gray wolves prey mainly on large ungulates, such as moose (Alces alces), deer (Odocoileus spp.), elk (Cervus elaphus), and caribou (Rangifer tarandus).  They tend to prey on the young, old, and sick members of ungulate populations.  Beaver (Castor canadensis) are a major supplement to gray wolves' diets [23].  Voigt and others [33] reported that gray wolves' diets vary, depending on relative prey abundance.  Other prey species include mountain goats (Oreamnos americanus), bison (Bison bison), pronghorn (Antilocapra americana), various rodents, upland game birds and waterfowl, snowshoe hare (Lepus americanus), and black bear (Ursus americana) [6,10,21,23,25,33]. On Isle Royale seeds of wild sarsaparilla (Aralia nudicaulis) were found in gray wolf scat [7].  Occasionally gray wolves prey on domestic livestock. PREDATORS : Humans are the only significant predator of the gray wolf and have eradicated it from almost all of its former range worldwide [27,34].  Pimlott and others [26] noted black bear preying on gray wolf cubs and adults. MANAGEMENT CONSIDERATIONS : Organized efforts to kill all the remaining gray wolves in the western United States began in the 1860's.  Yellowstone and Glacier National Parks established an official predator-control policy between 1914 and 1926 [27].  Today both parks are included in the Northern Rocky Mountain Wolf Recovery Plan as two areas capable of sustaining viable wolf populations.  Bunnell and Kremsater [4] concluded that wolves need about 7,818 square miles (20,250 sq km) to maintain a viable population of 50 individuals.  Fear of livestock depredation seems to be the single most cause of opposition to gray wolf recovery.  Also hunters worry that game will be less available if gray wolves were to recolonize their former ranges.  In Minnesota, northwestern Montana, central Idaho, and the Greater Yellowstone Ecosystem, livestock owners are reimbursed for animals taken by gray wolves [27].  An economic analysis conducted by Duffield [36] concluded that gray wolf reintroduction could possibly reduce the number of hunting permits, but that revenues lost would not exceed revenues gained from tourism in and around Yellowstone Park, due to the increase in photographers, filmmakers, and others wanting to see gray wolves.


DIRECT FIRE EFFECTS ON ANIMALS : No direct fire effects on gray wolves have been noted.   HABITAT RELATED FIRE EFFECTS : The effect of fire on gray wolf habitat is best defined by how fire affects gray wolves' prey.  Beaver, elk, moose, and deer are fire-dependent species, requiring the plant communities that persist following frequent fires [14,17].  Edwards [8] reported that after fire moose populated the area around Wells Gray Park, British Columbia, where they were previously unknown.  This was followed by a marked increase in gray wolves.  Other studies in Alaska, Michigan, Minnesota, and Canada show an increase in moose populations following fire [14,15,32]. Now absent from the old-growth forests of Minnesota, caribou once were an important prey for gray wolves here.  These forests do not provide enough food to sustain other ungulates for gray wolves to prey on.  Due to fire exclusion, these old-growth forested areas have increased, checking ungulate populations and consequently limiting gray wolf populations [15]. FIRE USE : Fire can be used to create browse for ungulates which, in turn, provides prey for gray wolves.  In Minnesota Heinselman [15] concluded that enough early postfire plant communities must exist within a gray wolf pack's territory to support a surplus of deer, moose, and beaver for prey. Adequate hiding cover should be maintained for the ungulates.  If they are abundant then gray wolf populations have a better chance of thriving. Gray wolves prosper best when they have a large area, relatively free from human disturbance, in which to roam, and when there is a surplus of ungulates [16].  Frequent fires that promote ungulate browse in and around areas that are at least moderately remote offer ideal gray wolf habitat. FIRE REGIMES : Find fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes".

References for species: Canis lupus

1. Ballard, Warren B.; Whitman, Jackson S.; Gardner, Craig L. 1987. Ecology of an exploited wolf population in south-central Alaska. Wildlife Monographs No. 98. Washington, DC: The Wildlife Society. 54 p. [13865]
2. Berg, William E.; Kuehn, David W. 1982. Ecology of wolves in northeast Minnesota. In: Harrington, Fred H.; Paquet, Paul C., eds. Wolves of the world: Perspectives of behavior, ecology, and conservation. Park Ridge, NJ: Noyes Publications: 4-11. [13868]
3. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals, reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's associations for the eleven western states. Tech. Note 301. Denver, CO: U.S. Department of the Interior, Bureau of Land Management. 169 p. [434]
4. Bunnell, Fred L.; Kremsater, Laurie L. 1990. Sustaining wildlife in managed forests. Northwest Environmental Journal. 6(2): 243-269. [12830]
5. Burt, William H.; Grossenheider, Richard P. 1976. A field guide to the mammals. Boston, MA: Houghton Mifflin. 289 p. [13685]
6. Cohn, Jeffrey P. 1990. Endangered wolf population increases. Bioscience. 40(9): 628-632. [13887]
7. Edwards, Joan. 1985. Effects of herbivory by moose on flower and fruit production of Aralia nudicaulis. Journal of Ecology. 73: 861-868. [13626]
8. Edwards, Joan. 1985. Effects of herbivory by moose on flower and fruit production of Aralia nudicaulis. Journal of Ecology. 73: 861-868. [13626]
9. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Washington, DC: Society of American Foresters. 148 p. [905]
10. Fritts, Steven H.; Mech, L. David. 1981. Dynamics, movements, and feeding ecology of a newly protected wolf population in northwest Minnesota. Wildlife Monographs No. 80. Washington, DC: The Wildlife Society. 79 p. [13863]
11. Fuller, Todd K. 1989. Population dynamics of wolves in northcentral Minnesota. Wildlife Monographs No. 105. Washington, DC: The Wildlife Society. 41 p. [13864]
12. Fuller, Todd K. 1988. Denning behavior of wolves in northcentral Minnesota. The American Midland Naturalist. 121: 184-188. [13867]
13. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others]. 1977. Vegetation and environmental features of forest and range ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of Agriculture, Forest Service. 68 p. [998]
14. Hansen, H. L.; Krefting, L. W.; Kurmis, V. 1973. The forest of Isle Royale in relation to fire history and wildlife. Tech. Bull. 294; Forestry Series 13. Minneapolis, MN: University of Minnesota, Agricultural Experiment Station. 44 p. [8120]
15. Heinselman, Miron L. 1973. Fire in the virgin forests of the Boundary Waters Canoe Area, Minnesota. Quaternary Research. 3: 329-382. [282]
16. Herman, Margaret, Willard, E. Earl. 1978. Rocky Mountain wolf and its habitat. Missoula, MT: U.S. Department of Agriculture, Forest Service, National Forest System Cooperative Forestry, Forestry Research, Region 1. 17 p. [16522]
17. Kramp, Betty A.; Patton, David R.; Brady, Ward W. 1983. The effects of fire on wildlife habitat and species. RUN WILD: Wildlife/ habitat relationships. Albuerque, NM: U.S. Department of Agriculture, Forest Service, Southwestern Region, Wildlife Unit Technical Report. 29 p. [152]
18. Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation of the conterminous United States. Special Publication No. 36. New York: American Geographical Society. 77 p. [1384]
19. Mech, L. David; Frenzel, L. D., Jr. 1971. The possible occurrence of the great plains wolf in northeastern Minnesota. In: Mech, L. David; Frenzel, L. D., Jr., eds. Ecological studies of the timber wolf in northeastern Minnesota. Res. Pap. NC-52. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station: 60-62. [13891]
20. Mech, L. David; Frenzel, L. D., Jr.; Ream, Robert R.; Winship, John W. 1971. Movements, behavior, and ecology of timber wolves in northeastern Minnesota. In: Mech, L. David; Frenzel, L. D., Jr., eds. Ecological studies of the timber wolf in northeastern Minnesota. Res. Pap. NC-52. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station: 1-35. [13888]
21. Mech, L. David. 1973. Wolf numbers in the Superior National Forest of Minnesota. Res. Pap. NC-97. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station. 10 p. [13885]
22. Mech, L. David. 1974. Canis lupus. Mammalian Species. 37: 1-6. [13866]
23. Mech, L. David; Karns, Patrick D. 1977. Role of the wolf in a deer decline in the Superior National Forest. Res. Pap. NC-148. St. Paul, MN: U.S. Department of Agriculture, Forest Service,North Central Forest Experiment Station. 23 p. [13886]
24. Mech, L. David. 1982. The IUCN-SSC wolf specialist group. In: Harrington, Fred H.; Paquet, Paul C., eds. Wolves of the world: Perspectives of behavior, ecology, and conservation. Park Ridge, NJ: Noyes Publications: 327-333. [13870]
25. Meehan, William R. 1974. The forest ecosystem of southeast Alaska: 4. Wildlife habitats. Gen. Tech. Rep. PNW-16. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 32 p. [13479]
26. Pimlott, D. H.; Shannon, J. A.; Kolenosky, G. B. 1969. The ecology of the timber wolf in Algonquin Provincial Park. Ottawa, ON: Candian Forestry Service, Department of Lands and Forests. 91 p. [13904]
27. Ream, Robert R.; Mattson, Ursula I. 1982. Wolf status in the northern Rockies. In: Harrington, Fred H.; Paquet, Paul C., eds. Wolves of the world: Perspectives of behavior, ecology, and conservation. Park Ridge, NJ: Noyes Publications: 362-381. [13871]
28. Robinson, William L.; Werner, J. Kirwin. 1975. Vertebrate animal populations of the McCormick Forest. Res. Pap. NC-118. St. Paul, MN: U.S. Department of Agriculture, Forest Service,North Central Forest Experiment Station. 25 p. [13484]
29. Scott, Barbara M. V.; Shackleton, David M. 1982. A preliminary study of the social organization of the Vancouver Island wolf. In: Harrington, Fred H.; Paquet, Paul C., eds. Wolves of the world: Perspectives of behavior, ecology, and conservation. Park Ridge, NJ: Noyes Publications: 12-24. [13869]
30. U.S. Department of the Interior, Fish and Wildlife Service. 2016. Endangered Species Program, [Online]. Available: [86564]
31. Van Ballenberghe, Victor. 1992. Conservation and management of gray wolves in the USA: status, trends, and future directions. In: McCullough, Dale R.; Barrett, Reginald H., eds. Wildlife 2001: populations. New York: Elsevier Applied Science: 1140-1149. [24226]
32. Viereck, Leslie A.; Schandelmeier, Linda A. 1980. Effects of fire in Alaska and adjacent Canada--a literature review. BLM-Alaska Tech. Rep. 6. Anchorage, AK: U.S. Department of the Interior, Bureau of Land Mangement, Alaska State Office. 124 p. [7075]
33. Voigt, Dennis R.; Kolenosky, George B.; Pimlott, Douglas H. 1976. Changes in summer foods of wolves in central Ontario. Journal of Wildlife Management. 40(4): 663-668. [13862]
34. Young, Stanley P.; Goldman, Edward A. 1944. The wolves of North America: parts I and II. New York: Dover Publishers. 636 p. [13861]
35. Zeveloff, Samuel I.; Collett, Farrell R. 1988. Mammals of the Intermountain West. Salt Lake, UT: University of Utah Press. 365 p. [13860]
36. Duffield, J. 1992. An economic analysis of wolf recovery in Yellowstone: Park visitor attitudes and values. In: Varley, J. D.; Brewster, W. G., eds. Wolves for Yellowstone? A report to the United States Congress. Vol. 4. Research and analysis. Yellowstone National Park, WY: U.S. Department of the Interior, National Park Service: pp. 2-35 to 2-87. [29422]
37. Fritts, Steven H. 1991. Wolves and wolf recovery efforts in the northwestern United States. Western Wildlands. 17(1): 2-6. [14252]
38. Washington Department of Wildlife. 1994. Species of special concern in Washington - state and federal status. Olympia, WA: Washington Department of Wildlife. 41 p. [25414]

FEIS Home Page